Need to get the latest data

Need to get the latest data

Can I query the latest 30 pieces of data without adding time, because the device may be offline for 3 days or more, and the time is uncertain

from(bucket: "abc")
|> range(start: -3d)
|> filter(fn: (r) => r["addr"] == "123456")
|> tail(n: 30)
|> difference()

Start with the Flux query in the issue, especially its range, tail, and difference operations. Determine whether the requested latest-30 behavior can be defined without a time bound, and document what successful behavior should be for devices offline for several days.

Written by the indexing model from the issue text.